xref: /linux/drivers/net/ethernet/freescale/fs_enet/mii-fec.c (revision 6e7fd890f1d6ac83805409e9c346240de2705584)
1 /*
2  * Combined Ethernet driver for Motorola MPC8xx and MPC82xx.
3  *
4  * Copyright (c) 2003 Intracom S.A.
5  *  by Pantelis Antoniou <panto@intracom.gr>
6  *
7  * 2005 (c) MontaVista Software, Inc.
8  * Vitaly Bordug <vbordug@ru.mvista.com>
9  *
10  * This file is licensed under the terms of the GNU General Public License
11  * version 2. This program is licensed "as is" without any warranty of any
12  * kind, whether express or implied.
13  */
14 
15 #include <linux/module.h>
16 #include <linux/types.h>
17 #include <linux/kernel.h>
18 #include <linux/string.h>
19 #include <linux/ptrace.h>
20 #include <linux/errno.h>
21 #include <linux/ioport.h>
22 #include <linux/slab.h>
23 #include <linux/interrupt.h>
24 #include <linux/delay.h>
25 #include <linux/netdevice.h>
26 #include <linux/etherdevice.h>
27 #include <linux/skbuff.h>
28 #include <linux/spinlock.h>
29 #include <linux/mii.h>
30 #include <linux/ethtool.h>
31 #include <linux/bitops.h>
32 #include <linux/platform_device.h>
33 #include <linux/property.h>
34 #include <linux/of.h>
35 #include <linux/of_address.h>
36 #include <linux/of_mdio.h>
37 #include <linux/pgtable.h>
38 
39 #include <asm/irq.h>
40 #include <linux/uaccess.h>
41 #include <asm/mpc5xxx.h>
42 
43 #include "fs_enet.h"
44 #include "fec.h"
45 
46 /* Make MII read/write commands for the FEC.
47 */
48 #define mk_mii_read(REG)	(0x60020000 | ((REG & 0x1f) << 18))
49 #define mk_mii_write(REG, VAL)	(0x50020000 | ((REG & 0x1f) << 18) | (VAL & 0xffff))
50 #define mk_mii_end		0
51 
52 #define FEC_MII_LOOPS	10000
53 
54 static int fs_enet_fec_mii_read(struct mii_bus *bus , int phy_id, int location)
55 {
56 	struct fec_info* fec = bus->priv;
57 	struct fec __iomem *fecp = fec->fecp;
58 	int i, ret = -1;
59 
60 	BUG_ON((in_be32(&fecp->fec_r_cntrl) & FEC_RCNTRL_MII_MODE) == 0);
61 
62 	/* Add PHY address to register command.  */
63 	out_be32(&fecp->fec_mii_data, (phy_id << 23) | mk_mii_read(location));
64 
65 	for (i = 0; i < FEC_MII_LOOPS; i++)
66 		if ((in_be32(&fecp->fec_ievent) & FEC_ENET_MII) != 0)
67 			break;
68 
69 	if (i < FEC_MII_LOOPS) {
70 		out_be32(&fecp->fec_ievent, FEC_ENET_MII);
71 		ret = in_be32(&fecp->fec_mii_data) & 0xffff;
72 	}
73 
74 	return ret;
75 }
76 
77 static int fs_enet_fec_mii_write(struct mii_bus *bus, int phy_id, int location, u16 val)
78 {
79 	struct fec_info* fec = bus->priv;
80 	struct fec __iomem *fecp = fec->fecp;
81 	int i;
82 
83 	/* this must never happen */
84 	BUG_ON((in_be32(&fecp->fec_r_cntrl) & FEC_RCNTRL_MII_MODE) == 0);
85 
86 	/* Add PHY address to register command.  */
87 	out_be32(&fecp->fec_mii_data, (phy_id << 23) | mk_mii_write(location, val));
88 
89 	for (i = 0; i < FEC_MII_LOOPS; i++)
90 		if ((in_be32(&fecp->fec_ievent) & FEC_ENET_MII) != 0)
91 			break;
92 
93 	if (i < FEC_MII_LOOPS)
94 		out_be32(&fecp->fec_ievent, FEC_ENET_MII);
95 
96 	return 0;
97 
98 }
99 
100 static int fs_enet_mdio_probe(struct platform_device *ofdev)
101 {
102 	struct resource res;
103 	struct mii_bus *new_bus;
104 	struct fec_info *fec;
105 	int (*get_bus_freq)(struct device *);
106 	int ret = -ENOMEM, clock, speed;
107 
108 	get_bus_freq = device_get_match_data(&ofdev->dev);
109 
110 	new_bus = mdiobus_alloc();
111 	if (!new_bus)
112 		goto out;
113 
114 	fec = kzalloc(sizeof(struct fec_info), GFP_KERNEL);
115 	if (!fec)
116 		goto out_mii;
117 
118 	new_bus->priv = fec;
119 	new_bus->name = "FEC MII Bus";
120 	new_bus->read = &fs_enet_fec_mii_read;
121 	new_bus->write = &fs_enet_fec_mii_write;
122 
123 	ret = of_address_to_resource(ofdev->dev.of_node, 0, &res);
124 	if (ret)
125 		goto out_res;
126 
127 	snprintf(new_bus->id, MII_BUS_ID_SIZE, "%pap", &res.start);
128 
129 	fec->fecp = ioremap(res.start, resource_size(&res));
130 	if (!fec->fecp) {
131 		ret = -ENOMEM;
132 		goto out_fec;
133 	}
134 
135 	if (get_bus_freq) {
136 		clock = get_bus_freq(&ofdev->dev);
137 		if (!clock) {
138 			/* Use maximum divider if clock is unknown */
139 			dev_warn(&ofdev->dev, "could not determine IPS clock\n");
140 			clock = 0x3F * 5000000;
141 		}
142 	} else
143 		clock = ppc_proc_freq;
144 
145 	/*
146 	 * Scale for a MII clock <= 2.5 MHz
147 	 * Note that only 6 bits (25:30) are available for MII speed.
148 	 */
149 	speed = (clock + 4999999) / 5000000;
150 	if (speed > 0x3F) {
151 		speed = 0x3F;
152 		dev_err(&ofdev->dev,
153 			"MII clock (%d Hz) exceeds max (2.5 MHz)\n",
154 			clock / speed);
155 	}
156 
157 	fec->mii_speed = speed << 1;
158 
159 	setbits32(&fec->fecp->fec_r_cntrl, FEC_RCNTRL_MII_MODE);
160 	setbits32(&fec->fecp->fec_ecntrl, FEC_ECNTRL_PINMUX |
161 	                                  FEC_ECNTRL_ETHER_EN);
162 	out_be32(&fec->fecp->fec_ievent, FEC_ENET_MII);
163 	clrsetbits_be32(&fec->fecp->fec_mii_speed, 0x7E, fec->mii_speed);
164 
165 	new_bus->phy_mask = ~0;
166 
167 	new_bus->parent = &ofdev->dev;
168 	platform_set_drvdata(ofdev, new_bus);
169 
170 	ret = of_mdiobus_register(new_bus, ofdev->dev.of_node);
171 	if (ret)
172 		goto out_unmap_regs;
173 
174 	return 0;
175 
176 out_unmap_regs:
177 	iounmap(fec->fecp);
178 out_res:
179 out_fec:
180 	kfree(fec);
181 out_mii:
182 	mdiobus_free(new_bus);
183 out:
184 	return ret;
185 }
186 
187 static void fs_enet_mdio_remove(struct platform_device *ofdev)
188 {
189 	struct mii_bus *bus = platform_get_drvdata(ofdev);
190 	struct fec_info *fec = bus->priv;
191 
192 	mdiobus_unregister(bus);
193 	iounmap(fec->fecp);
194 	kfree(fec);
195 	mdiobus_free(bus);
196 }
197 
198 static const struct of_device_id fs_enet_mdio_fec_match[] = {
199 	{
200 		.compatible = "fsl,pq1-fec-mdio",
201 	},
202 #if defined(CONFIG_PPC_MPC512x)
203 	{
204 		.compatible = "fsl,mpc5121-fec-mdio",
205 		.data = mpc5xxx_get_bus_frequency,
206 	},
207 #endif
208 	{},
209 };
210 MODULE_DEVICE_TABLE(of, fs_enet_mdio_fec_match);
211 
212 static struct platform_driver fs_enet_fec_mdio_driver = {
213 	.driver = {
214 		.name = "fsl-fec-mdio",
215 		.of_match_table = fs_enet_mdio_fec_match,
216 	},
217 	.probe = fs_enet_mdio_probe,
218 	.remove_new = fs_enet_mdio_remove,
219 };
220 
221 module_platform_driver(fs_enet_fec_mdio_driver);
222 MODULE_LICENSE("GPL");
223